She told Channel Seven the other vehicle "came up on the inside of us, clipped the car and our car just lost control and it just started spinning and we took out all those people".

"It was so bad."

The drivers of both vehicles were being interviewing by police on Sunday night.

Ian and Helen Barr were metres from the scene with their two-year-old granddaughter when the crash occurred.

They had just crossed the road from Flagstaff Gardens when they heard two loud bangs. If they had taken a slightly different route, they could have been struck, Mrs Barr said.

"It gives you a bit of a shock," she said. "You just think, in one moment your life could be gone. I just thought, it's just the way you walk."

Mrs Barr, who is visiting Melbourne from Portarlington, said she was relieved no one had been killed.

"I thought it would've been a fatality for sure," she said.

"It's just fate isn't it and because we had our granddaughter with us, it could've been worse."

A preschool-aged girl was treated for abrasions to her face and legs and was taken to the Royal Children's Hospital in a stable condition.

A woman in her 30s was treated for leg and back soreness, and was taken to hospital in a serious but stable condition.

A man in his 30s was treated for leg injuries and a woman in her 30s was treated for injuries to her ribs and chest.

The adult patients were taken to the Royal Melbourne and St Vincent's hospitals.

One adult has serious but non-life-threatening injuries, while a second adult and two children have minor injuries.

The RACV said it was very concerned for the health and wellbeing of all people involved in the incident.

The RACV would offer assistance where it could, a spokesman said.

Anyone who witnessed the incident can contact Crime Stoppers on 1800 333 000.